[23.03] A Keck mid-IR survey of FR-II AGN

We present the preliminary results from imaging a complete
sample of 3CR FR-II radio galaxies and quasars using Keck I
LWS. Observations in the mid-IR are sensitive to thermal
emission from warm dust. In radio galaxies where the dusty
torus obscures the nucleus, the mid-IR emission can be used
as a calorimeter to estimate the optical/UV emission of an
obscured quasar-like nucleus. The majority of narrow line
radio galaxies are not detected. This suggests that the bulk
kinetic power of the radio jets is the energetically
dominant mechanism in many objects, and that thermal
accretion is often not the dominant energy source.